Presser foot for sewing machines



May 26, 1959 M. T. VOIGT PRE ISSEIR FOOT FOR SEWING MACHINES Filed April27, 1956 4 INVENTOR.

11 TTORNEY United States Patent PRESSER FOOT FOR SEWING MACHINES Thisinvention relates generally to presser foot devices for sewing machinesand more particularly to improvements in compensating presser footdevices.

This type of presser foot commonly is provided with a pair of. mainpresser shoes that are mounted side by side and independently biasedtoward the work, being provided respectively with a pair of opposed workguiding edges. Such a presser foot permits the use of a sewing machineto form a line of stitches in a portion of cloth of varying thickness,as at a seam or edge, and maybe used on either right hand or left handedges of a cloth, obviating the necessity for reversing the cloth forrunning a line of stitches. Known compensating foot devices have notproved to be entirely satisfactory because after the work has beencompletely stitched and advanced beyond the presser foot, the stitchforming thread is not chained off as is customary with a solid presserfoot. Accordingly, a principal object of the present invention is toprovide a compensating presser foot with means for positively feedingthe thread past the compensating presser foot after the work has beencompletely stitched and advanced beyond the presser foot, so that thethread is chained off as is customary with a solid presser foot.

Other objects and advantages of the present invention will 'appear morefully hereinafter, it being understood that the invention consistssubstantially in the combination, construction, location and relativearrangement of parts, all as described in the accompanying drawings andas finally pointed out in the appended claims.

In the accompanying drawings:

-Figure 1 is a vertical longitudinal section through one form of acompensating presser foot constructed in accordance with and embodyingthe principles of the present invention, as indicated by line 11 ofFigure 2;

Figure 2 is a vertical transverse section of the compensating presserfoot shown in Figure l, as indicated by line 2--2 of Figure 1;

Figure 3 is a fragmentary vertical section taken on line 3-3 of Figure2;

Figure 4 is a horizontal section taken on line 4-4 of Figure 1;

Figure 5 is a perspective view of the intermediate presser shoe of theembodiment shown in Figures 1 through 4 and 6 through 8;

Figure 6 is a horizontal section showing a garment being passed underthe intermediate and right hand presser shoes while being guided by theleft hand presser shoe;

Figure 7 is the same as Figure 6, but shows the garment being passedunder the intermediate and left hand Figure 9 is similar to Figure 1,but shows a modified form of the invention;

Figure 10 is similar to Figure 4, but relates to the modification shownin Figure 9;

Figure 11 is a perspective view of the intermediate presser shoe of theembodiment shown in Figures 9 and 10;

Figure 12 is similar to Figures 1 and 9, but shows a second modifiedform of the invention;

Figure 13 is similar to Figure 2, but relates to the modification shownin Figure 12;

Figure 14 is a plan view of the modification shown in Figure 12;

Figure 15 is similar to Figures 4 and 10, but relates to themodification shown in Figures 12, 13 and 14; and

Figure 16 is a perspective view of the intermediate presser shoes ofthe' embodiment shown in Figures 12 through 15.

Referring to the drawing, each form of the compensating presser footconstructed in accordance with and embodying the present inventioncomprises a shank 10 made to interfit with the supporting parts of anyone of the numerous types of sewing machines now on the market. At thelower end, shank 10 carries a yoke 11 of inverted U-shape in verticalcross section having the side walls 1212, which are pierced by holesthrough which passes a pivot 13.

Mounted on pivot 13 are a pair of substantially duplicate presser shoes14 and 14a positioned side by side between the side walls 1212 of theyoke 11. Each of these shoes has a body 15 provided with a vertical slot16 so as to support the presser shoe on the pivot 13. The presser shoeis provided with a fiat sole 17 or 17a and with an upturned toe 18 or18a. The opposed sides of the shoes 14 and 14a are undercut so as toform a horizontally longitudinally extending groove 19 having oppositeside walls 20 and 20a. In its upper surface, the presser shoe isrecessed to receive two springs 21-21 shown as coil springs, althoughthey may be of any convenient type which serve to urge the presser shoeto the limit of'its movement away from the yoke 11, and which also serveto oppose pivotal movement of the presser shoe about the pivot 13.

Now referring to the embodiments of the present invention shown inFigures 1 through 8, and particularly to Figure 5, the presser foot isprovided with an auxiliary presser member, designated generally by thenumeral 22', disposed centrally between the presser shoes 14 and 14a andfuntioning in effect as a third presser shoe. The third presser shoeconsists of a length of flat spring metal bent to a generallyrectangular shape, the opposite end portions 23-23 thereof being broughttogether to form presser shoes while being guided by the right handpresser shoe; I

Figure 8 is the same as Figure 6, but shows the garment just startingunder the presser foot, and the thread in advance of the garmentpositively fed beyond the presser foot;

the upper side of the rectangle, and being inclined upwardly toward oneanother.

The member 22 extends about the opposed side portions of the pressershoes 14 and 14a with the lower side thereof freely received in thegroove 19 and its opposite ends 2525 respectively disposed in verticallyextending relation at the front and rear of the bodies 15-15 of theshoes 14 and 14a. The upper portions of the auxiliary shoe, i.e., theopposite end portions 23-23, are freely received between the tops of thebodies 15-15 of the shoes 14 and 14a and the base or under surface 26 ofthe yoke 11, as shown. The lower side 24 of the shoe 22 is the effectiveworking part thereof and is operatively disposed between the shoe soles17 and 17a, which are the effective working parts respectively of theshoes 14' and 14a.

It will be observed that the opposite side presser shoes 14 and 14a andthe intermediate presser shoe 22 may be raised simultaneously againstthe influence of the sev-,

1 eral coil springs 21 and the inherent bias of the presser shoe 22.Furthermore, the intermediate presser shoe and either of the oppositeside presser shoes may be raised simultaneously independently of theother opposite side presser shoe.

Now referring to Figures 6, 7 and 8, and particularly to Figures 6 and8, when it is desired to sew along the left hand edge of the garment orother work, the latter, designated W, is passed under the intermediatepresser shoe 22 and the presser shoe on the right thereof, i.e., thepresser shoe 14. During this operation, the side wall 20a of the shoe14a serves to guide the work and assure spacing of the line of stitches27 a uniform distance from the edge 28 of the work. It will beunderstood that the work W passing under the presser shoes 14 and 22raises these presser shoes relative to the presser shoe 14a a distanceequal to the thickness of the work W. As the stitching is formed, theline thereof passes under the intermediate presser shoe, which overliesthe feed dog (not shown) which projects upwardly through the throatplate of the sewing machine.

Now referring particularly to Figure 7, when it is desired to sew alongthe right hand edge of the garment or other work W, the latter is passedunder the intermediate presser shoe 22 and the presser shoe on the leftthereof, i.e., the presser shoe 14a. During this operation, the sidewall 20 of the shoe 14 serves to guide the work and assure spacing ofthe line of stitches 29 a uniform distance from the edge 30 of the work.It will be understood that the work W passing under the presser shoes14a and 22 raises these presser shoes relative to the presser shoe 14 adistance equal to the thickness of the work W, and that the formedstitching passes under the intermediate presser shoe, which, as alreadypointed out, overlies the feed dog of the sewing machine.

While the work W is passing under the presser foot, the intermediatepresser shoe 22, in association with that one of the shoes 14-1411 whichoverlies the work, coacts with the underlying feed dog to positivelyfeed the work through the machine for the required stitching thereof.After the stitched work has passed from under the presser foot, theintermediate presser shoe 22 is returned to its normal position underthe influence of its inherent bias and continues without interruption tocoact with the underlying feed dog to positively feed the stitch-formingthreads from their respective bobbins. Since the thread is positivelyfed past the presser foot whether or not the Work W is actually passingunder the presser foot, it is unnecessary to manually draw thread fromthe machine after the work has passed under the presser foot, inconsequence of which the operator does not risk breaking, with all itsattending inconvenience and loss of time.

Now referring to the embodiment of the present invention shown inFigures 9, l0 and 11, and particularly to Figure 11, the intermediatepresser foot, designated generally by the numeral 31, consists of alength of fiat spring metal bent to generally U-shape, having oppositeside portions 32 and 33 connected together by a portion 34, the portions33 and 34 being of reduced width. The portion 32 extends horizontallyfrom rear to front through the yoke 11, close under the base surface 26of the latter, the portion 34 extends downwardly from the portion 32along the front of the bodies 3515 of the presser shoes 14 and 14a, andthe portion 33 extends from front to rear freely through the groove 19between the presser shoes 14 and 14a, sloping downwardly to a curvedterminal portion 35. The sloping lower portion 33 of the intermediatepresser shoe 31 is the elfective working part there of, the curvedterminal portion 35 being forced upwardly when the Work W passesthereunder.

Now referring to the embodiment of the present invention shown inFigures 12 through 16, the intermediate p'resser foot, designatedgenerally by the numeral 36, consists of a length of flat spring metal,having an intermediate portion 37 extending freely through the groove 19between the presser shoes 14 and 14a, a front end portion 38 extendingupwardly in front of the bodies 1515 of the presser shoes 14 and 14a,and a rear end portion 39 laterally offset from the intermediate portion37. This intermediate portion 37 is the effective working part of theintermediate presser shoe 36, which latter is yieldably biaseddownwardly by a pressure rod including a member 40 that is secured tothe rear end portion 39 of the presser shoe 36, a guide 41 slidablymounting the member 40, and a coil spring 42 wrapped around the member40.

In view of the description of the operation of the embodiment shown inFigures 1 through 8, it is believed that a detailed description of theoperation of the modified forms of the invention is unnecessary for afull understanding of the present invention.

It will be noted that in all forms of the construction as illustrated,the Work-guiding edges of the outer presser shoes 14-1411 areequidistantly spaced from the line of stitching, thereby insuring thatthe stitch line as formed along any guided edge of the work is spaced auniform distance within said edge. Obviously, by changing the transversewidth of the intermediate auxiliary presser member or shoe 22, thedistance between the stitch line and the guided edge of work may becorrespondingly changed.

Also, it will be evident that by employing an intermediate member 22which is laterally olfset relatively to the vertical plane of the sewingmachine needle, i.e., to the stitch line, in association with outerpresser shoes 14-l4a having guide edges approximately coincident withthe opposite parallel edges of the member 22, the spacing of the stitchline adjoining one guided edge of the work will be different from thatadjoining the opposite guided edge of the work. Thus, the three pressershoes 14, 14a and 22 may be so relatively arrangedasto provide a stitchline which is spaced say A; of an inch from a guided edge of the Workwhen one of the outer shoes is employed as a guide and to provide astitch line spacing of say of an inch when the other outer shoe isemployed as a guide.

An important advantage of the presser foot 'as constructed in accordancewith the present invention. is that it eliminates completely anypossibility of the stitchforming thread becoming wedged between theproximate edges of the main presser shoes, this because of the fact thatthe intermediate spring-pressed member or shoe 22 overlies the verticalplane of division between saidmain presser shoes.

It will be understood, of course, that the present invention ashereinbefore described and shown in the accompanying drawings issusceptible of various changes and modifications which may be made fromtime to time without departing from the general principles or realspirit of the invention, and accordingly, it is intended to claim thesame broadly, as well as specifically, as indicated in the appendedclaims.

What is claimed as new and useful is:

1. In a compensating presser foot for sewingmachines, an upright axiallyfixed shank forming the support for said presser foot, a set of threeseparate presser shoes carried by said shank and mounted upon the lowerextremity thereof in side by side relation, means for mounting the twoopposite side presser shoes for rectilinear shifting movementindependently of one another and of the intermediate shoe bodily axiallyof said shank and for pivotal movement independently of one another andof said intermediate shoe bodily about an axis extending transversely ofsaid shank, said interme presser shoe being provided with an effectiveWOI pg portion shiftable bodily axially of said shank with either orboth of said two opposite side presser shoes, and means operatively.interposed between said shank and presser shoes and operating to biassaid two opposite side presser shoes and said working portion of theintermediate presser shoe to the limit of their downward movement,independently of one another, axially of said shank.

2. In a compensating presser foot for sewing machines, an uprightaxially fixed shank forming a support for said presser foot, a pair ofseparate presser shoes, means mounting said presser shoes in side byside relation at the lower extremity of said shank for independentreciprocating and pivotal movement in a vertical plane relative to oneanother and to said shank, yieldable means operatively interposedbetween said shank and pair of presser shoes and operating to urge thelatter to the limit of their downward movement away from said shank andto yieldably oppose pivotal movement thereof, and a third presser shoein the form of a leaf spring wrapped commonly around opposed sideportions of said pair of shoes, the opposite end portions of said leafspring being thereby positioned between said shank and pair of pressershoes, and an intermediate portion of said leaf spring being positionedflatwise between the working portions of said pair of presser shoes tothereby serve as the effective working portion of said third pressershoe.

3. In a compensating presser foot for sewing machines as defined inclaim 2 wherein the opposed side portions of said pair of presser shoesare undercut to form a groove extending fore and aft of the presser footand having side walls adapted to serve as guides for the work, and theleaf spring third presser shoe is generally rectangular in shape, oneside of the leaf spring being received in said groove and the oppositeside being received between said shank and the tops of said pair ofpresser shoes, said opposite side of the rectangular leaf spring beingin the form of opposite end portions of said leaf spring convergingupwardly away from said pair of presser shoes.

4. The presser foot according to claim 2 wherein said intermediatepresser shoe is in the form of a leaf spring and said effective workingportion is positioned between the working portions of said side pressershoes and normally slopes upwardly and forwardly from a free end portionthereof at the rear of said intermediate presser shoe.

5. In a compensating presser foot for sewing machines as defined inclaim 4 wherein the opposed side portions of said side presser shoes areundercut to form a groove extending fore and aft of the presser foot andhaving side Walls adapted to serve as guides for the work, and the leafspring intermediate presser shoe is generally U- shaped, the efiectiveworking portion of said leaf spring presser shoe being one arm of saidU-shaped member disposed in said groove, the opposite arm of said U-shaped member being disposed between said shank and said biasing meansand the connecting portion between the arms of said U-shaped memberbeing positioned upright in advance of the sides of said U-shaped leafspring.

6. In a compensating presser foot for sewing machines, an uprightaxially fixed shank forming a support for said presser foot, a pair ofseparate presser shoes, means mounting said presser shoes in side byside relation at the lower extremity of said shank for independentreciproeating and pivotal movement in a vertical plane relative to oneanother and to said shank, yieldable means opatively interposed betweensaid shank and pair of presser shoes and operating to urge the latter tothe limit of their downward movement away from said shank and toyieldably oppose pivotal movement thereof, a third presser shoeoperatively interposed between said pair of presser shoes and mountedfor independent reciprocating movement in a vertical plane relative tosaid pair of presser shoes and to said shank, yieldable meansoperatively interposed between said shank and third presser shoe andoperating to urge the latter to the limit of its movement downwardlyaway from said shank.

7. In a compensating presser foot for sewing machines as defined inclaim 6 wherein the opposed side portions of said pair of presser shoesare undercut to form a groove extending fore and aft of the presser footand having side walls adapted to serve as guides for the work, the thirdpresser shoe extends through said groove, and the yieldable meansinterposed between said shank and third presser shoe is a pressure rod.

References Cited in the file of this patent UNITED STATES PATENTS955,962 Grieb Apr. 26, 1910 1,202,283 Gray Oct. 24, 1916 1,243,809Chalman Oct. 23, 1917 2,288,051 Voigt June 30, 1942 2,384,454 CosentinoSept. 11, 1945 2,446,852 Sailor Aug. 10, 1948

